I am a Master of Mathematics (Computer Science) student at the University of Waterloo where I am supervised by Dr. Edith Law. I earned my Bachelor of Science (Honors) at The University of Western Ontario with an Honors Specialization in Computer Science and a Major in Microbiology and Immunology.

In general, my research interests include:

  • Applied Machine Learning
  • Big Data & Graph Analytics
  • Health Informatics
  • Human-In-The-Loop Systems

I am specifically motivated by time-series related problems across various domains. Currently, I'm working on a project which explores methods of combining humans and machine learning algorithms for the analysis of heart sound recordings.

Invited Speaker

  1. Callaghan, W. (2017). Fighting Cybercrime: A Joint Task Force of Real Time Data and Human Analytics. Presented at the Databricks Spark Summit East Conference, Boston, MA. More Info  Video


Workshop Papers

  1. Schaekermann, M., Law, E., Williams, A. C., & Callaghan, W. (2016). Resolvable vs. Irresolvable Ambiguity: A New Hybrid Framework for Dealing with Uncertain Ground Truth. In 1st Workshop on Human-Centered Machine Learning at SIGCHI 2016. San Jose, CA. PDF

  2. Williams, A. C., Bradshaw, J., Schaekermann, M., Tse, T., Callaghan, W., & Law, E. (2016). The Big Picture: Preserving Context in the Decomposition of Complex Expert Tasks. In 1st Workshop on Microproductivity at SIGCHI 2016. San Jose, CA. PDF


  1. Callaghan, W. (2015). Using Kalman Filtering and Lasso Regularization to Generate Brain Networks (Bachelor's thesis, University of Western Ontario, London, Canada). PDF